summaryrefslogtreecommitdiffstats
path: root/build/docs/pgo.rst
diff options
context:
space:
mode:
Diffstat (limited to 'build/docs/pgo.rst')
-rw-r--r--build/docs/pgo.rst28
1 files changed, 28 insertions, 0 deletions
diff --git a/build/docs/pgo.rst b/build/docs/pgo.rst
new file mode 100644
index 0000000000..722056c727
--- /dev/null
+++ b/build/docs/pgo.rst
@@ -0,0 +1,28 @@
+.. _pgo:
+
+===========================
+Profile Guided Optimization
+===========================
+
+:abbr:`PGO (Profile Guided Optimization)` is the process of adding
+probes to a compiled binary, running said binary, then using the
+run-time information to *recompile* the binary to (hopefully) make it
+faster.
+
+How PGO Builds Work
+===================
+
+The supported interface for invoking a PGO build is to add ``MOZ_PGO=1`` to
+configure flags and then build. e.g. in your mozconfig::
+
+ ac_add_options MOZ_PGO=1
+
+Then::
+
+ $ ./mach build
+
+This is roughly equivalent to::
+
+#. Perform a build with *--enable-profile-generate* in $topobjdir/instrumented
+#. Perform a run of the instrumented binaries with build/pgo/profileserver.py
+#. Perform a build with *--enable-profile-use* in $topobjdir